Subterranean drain

ABSTRACT

A SUBTERRANEAN DRAIN UNIT INCLUDING A DRAIN PIPE HAVING OPENINGS THEREIN AND A LONGITUDINALLY EXTENDING OLANAR CORE DEFINING CHANNELS NORMAL TO THE PIPE. SHEET MATERIAL COVERING AT LEAST THE CORE AND THE OPENINGS IN THE PIPE TO FORM A FILTER THEREFOR.

3 Sheets-Sheetl 1 v \`v v K. A. HEALY ETAL SUBTERRANEAN DRAIN RICHARD P LONG JM @/M/ Feb. 16, 1971 Filed April 5, 1969 FIG. 2

Feb. 16,1971 `K A, HEAD, ETAL 3,563,038

SUBT ERRANEAN DRAIN Filed April f5, 1969 I5 Sheets-Sheet 2 Fla 4 FIG. 5

"5 .I A INVENTORS vKENT A. HEALY RICHARD F? LONG BY mL/5 f ATTORNEY Fd. 16, 1971 K. A. HEALY ETAL.

SUBTERRANEAN DRAIN 3 Sheets-Sheet S Filed April 5. 1969 J Nv e w..

FIG. 8

INVENTOR.' KENT A. HEALY RICHARD I? LONG wlw ATTORNEY United States Patent O M' 3,563,038 SUBTERRANEAN DRAIN Kent A. Healy and Richard P. Long, Storrs, Coun., assignors, by mesne assignments, to Research Corporation, New York, N.Y., a foundation of New York Filed Apr. 3, 1969, Ser. No. 812,982 Int. Cl. E02b 11/00; B01d 35/02 U.S. Cl. 61-11 6 Claims ABSTRACT OF THE DISCLOSURE A subterranean drain unit including a drain pipe having openings therein and a longitudinally extending planar core defining channels normal to the pipe. Water pervious sheet material covering at least -the core and -the openings inthe pipe to form a filter therefor.

BACKGROUND OF THE INVENTION This invention pertains generally to subterranean drains and more particularly to drain systems for use in removing water from the vicinity of structural foundations and earthworks.

In order to stabilize structural foundations and earthworks, it is necessary to remove water penetrating the solid mass quickly, while avoiding a decrease in the strength of the soil through piping or pore pressure. Such removal is accomplished, at present, by means of drainage systems comprising drainage pipe surrounded by a mineral aggregate. The particle size distribution of the aggregate must be carefully matched `to the native soil in the region of construction. The functions of a properly designed drainage system are to remove water from the surrounding soil while filtering or preventing movement of soil particles therefrom. In known art, systems must also be designed such that the hydraulic gradient is kept sufficiently low that the aggregate or filter will not be disturbed.

Improper design causes clogging or other malfunctioning of prior art systems and the attendant deterioration of the structure. Such failures have been common due to the complexity and care required in designing and construction of the drainage system. The labor and time consumed in constructing such systems also adds to the expense of construction.

SUMMARY OF THE INVENTION The present invention provides a novel drainage unit which overcomes the disadvantages of -the prior art by providing a prefabrica-ted drainage system adapted for use in a variety of soil conditions.

The invention also furnishes a drainage system which is more reliable than in situ constructed systems by providing a system incorporating a prefabricated filtration medium which is suitable for use in soils of varying types.

The invention also provides a drainage system which is less costly in installation than prior art systems furnishing a prefabricated unit which can be installed by relatively unskilled personnel.

In a preferred embodiment, this invention provides a prefabricated drain unit comprising a drain pipe having openings therein; a planar longitudinal water channeling core, extending from the pipe and a filtering cover covering at least the core and Ithe openings in the pipe.

Other objects and many of the attendant advantages of this invention will become more apparent to those skilled in the art by reference to the following detailed description when viewed in the light of the accompanying drawings wherein like numerals throughout the figures indicate like components.

3,563,038 Patented Feb. 16, 1971 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view in section, of a drainage unit in accordance with the invention, installed beneath a Structure;

FIG. 2 is a fragmentary perspective view of the unit of FIG. l;

FIG. 3 is a sectional view of the unit of FIG. 2 taken along the line 3-3 thereof;

FIG. 4 is a fragmentary perspective view of another unit in accordance with the invention;

FIG. 5 is a sectional view of the unit of FIG. 4 taken along the line 5-5 thereof;

FIG. 6 is an elevational view, in section of the unit of FIG. 4 installed proximate a wall structure;

FIG. 7 is a view similar to FIG. 6 showing the unit of FIG. 4 installed proximate a foundation;

FIG. 8 is a fragmentary elevational view, partly broken away, of another unit in accordance with the invention; and

FIG. 9 is an enlarged sectional view of the unit of FIG. 8 taken along the line 9-9 thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. l, a drainage unit, shown generally at 10, is illustrated in place in a trench 12 beneath a slab 14. The unit is disposed vertically and is surrounded by backfill 16.

In FIGS. 2 and 3 the unit 10 comprises a core member, generally indicated at 18, and tubular pipe 20. In this embodiment the core 18 is formed from a sheet of corrugated or pleated material with the corrugations or pleats defining vertical channels 22 therein. The lower, longitudinal edge 24 of the sheet is rolled and terminates in spaced relationship to itself to form the pipe 20 with the remainder of the sheet forming the core 18. The space between the edge 24 and the core 18 defines a slot 26 along the pipe for the entrance of water coming down that side. Perforations are provided on the other side to allow entrance of water on that side. 'Ihe sheet may comprise any material which can be suitably formed into flow channels for the water and which is compatible with the environment with which the unit is to be used. Plastic or sheet metal 0.015 inch to 0.030 inch in thickness has been found particularly suited for use in connection with this invention. Square corrugations iis by 5/{16 inch in size and triangular pleats have also been found suited for the channels of the unit.

The unit 10 is encased by a pervious sheet material 28 which is preferably affixed thereto by adhesive or the like. The sheet material serves as a filter and is ideally formed of a synthetic fabric compatible with the environment in which the unit is used. In the event synthetic fabric is used as the filter, it is contemplated that the fabric can be afiixed to the core 18 by heat sealing if found desirable. The fabric should be selected with a suitable mesh and thickness that solid particles will be held back or pass through one opening but will not remain in a position so as to clog the openings.

As best seen in FIG. 2, the pipe 20 is provided with a series of openings 30 therealong to allow entrance of water from that side.

In FIGS. 4 and 5, another embodiment in accordance with the invention is shown. In this embodiment, components corresponding'to like components of the preceding embodiment are illustrated by like numerals, only of the next higher order.

The unit comprises a core member 118, formed of a light material such, for example, as foamed polystyrene, or the like. A pipe having openings 130 in the upper about abuts the lower edge of the core 118. The

\ pipe may be formed of any material suitable for the use such as ceramic, metal, or plastics. Where Weight, cost and handling characteristics are a factor, a lightweight plastic material is preferred. Channels 122 are formed in or cut into the planar surfaces of the core 118 and intersect the pipe 120. A pervious sheet material 128 encases the exposed surfaces of the pipe 120- and the core 118 to serve as a filter fabric as in the embodiment of FIGS. 2 and 3.

In FIG. 6, the unit 110 is shown emplaced behind a retaining wall 132 and surrounded by backiill 116. In this installation, the unit functions best with the core 118 displaced at an angle to the vertical as illustrated.

In FIG. 7, the unit 110 is vertically disposed in backill 116 behind a foundation 134.

Referring now to FIGS. 8 and y9, another embodiment in accordance with the invention is illustrated, in which components thereofcorresponding to like components of the preceding embodiments are indicated by like numerals, only of the next higher order. The unit 210 comprises a core member 218 and a drainage pipe 220. In this embodiment, the core 218 is formed of expanded sheet metal having openings 222 therein. The material may be plastic or metal and is formed by first slitting or perforating a sheet followed by stretching in the plane of the sheet in a manner well known in the art. The pipe 220 is provided with a slot 230l therealong in which the core 218 is disposed as is best seen in FIG. 9. A sheet of pervious material 228 is iixed to the upper surface of the pipe 220 by adhesive or the like, and encases the core 218 to serve as a iilter fabric, as in the embodiments of FIGS. 2 and 3.

As in the preceding embodiments, the core 218 serves as a means for channeling -uid into the pipe 220. In the instant embodiment, the channeling is provided by the openings 222 and the transverse dimension of the core 222 which is a product of the turning of the elements of the core during stretching, an inherent result of the expansion of the sheet metal in formation of the core. This transverse dimension and the openings 222 serve to space the material 228 so that fluid may drain therebetween.

From the aforegoing embodiments, it should be obvious that the core may consist of various suitable materials, cast, formed, machined, or otherwise fabricated to provide a iluid transmitting extension from the pipes to support the filter medium and to channel fluid filtered through the medium to the pipe.

In installation, units 10, 110 or 210 are placed proximate a structure for which drainage is required, for example, as shown in FIGS. 1, 6 or 7, suitably connected en-to-end to one another and to a drainage conduit, and then surrounded by backill more permeable than the surrounding earth. Water then penerates the backlill and enters through the permeable sheet material 28, 128 or 228 into the channels 22, 122 or 222 through which it is transmitted to the pipe 20, 120 or 220* for drainage to a drainage conduit (not shown).

The unit allows the objectives of the invention, e.g., suitable water flow and prevention of movement of soil particles, to be achieved in a more eiiicient manner than the prior art. The unit also eliminates the requirement of maintaining a low hydraulic gradient, since the lter cannot be disturbed by an adverse gradient.

What has been set forth above is intended primarily as exemplary of the teaching in accordance with the invention to enable those skilled in the art in the practice thereof. It should, therefore, be understood that, within the scope of the appended claims, the invention can be practiced other than as specifically described.

. What is new and therefore desired to be protected by Letters Patent of the United States is:

1. A subterranean drainage unit comprising:

(l) A primary subterranean liquid conveying member, said member comprising a generally cylindrical hollow drain pipe adopted to be positioned in the ground with the axis of the cylinder lying in a generally horizontal plane, and said member having liquid inlets extending through the cylindrical surface thereof;

(2) A planar extended surface core member longitudinally disposed along said drain pipe, liquid channelling means formed in said core member to transmit liquid to the interior of said drain pipe; and

(3) A covering of liquid pervious material encasing at least said core and its liquid channelling means.

2. A drainage unit as defined in claim 1 wherein said core is formed of sheet material, and said channel means comprising corrugations formed in said sheet.

3. A drainage unit in accordance with claim 2 wherein said pipe means is formed from a rectangular sheet with a pair of opposed edges thereof rolled into spaced, adjacent relationship to form a slotted tube, one of said rolled edges being contiguous with an edge of said core.

4. A drainage unit in accordance with claim 1 wherein said core comprises a panel, and said channel means comprising grooves formed across the opposed planar surfaces of said panel with said grooves extending normal to the cylindrical axis of the drain pipe.

5. A drainage unit in accordance with claim 4 wherein said panel is formed of foam plastic material.

6. A drainage unit in accordance with claim 1 wherein said core comprises a panel of expanded sheet material, said channel means being deiined by the openings and transverse deformations of said expanded sheet.

References Cited UNITED STATES PATENTS 1,323,027 11/1919 Davis 61--10 2,263,853 11/1941 Re Qua 210-486 2,426,618 9/ 1947 Klein 2l0-346X 2,482,673 9/1949 Kjellman 61-11 2,778,096 1/1957 Weema 29-163.5 3,268,990 8/1966 Adler 29--163.5 3,401,526 9/1968 Rodgers 61-13 3,461,675 8/1969 Izatt 6'1-11 FOREIGN PATENTS 655,385 1951 Great Britain 210--486l JACOB SHAPIRO, Primary Examiner U.C. Cl. X.R. 210-346, 486 

